EP2097038A2

EP2097038A2 - Method for producing a dental product, and scannable material

Info

Publication number: EP2097038A2
Application number: EP07856276A
Authority: EP
Inventors: Matthias Suchan; Alexander Bublewitz; Jens-Peter Reber
Original assignee: Kettenbach GmbH and Co KG
Current assignee: Kettenbach GmbH and Co KG
Priority date: 2006-11-28
Filing date: 2007-11-28
Publication date: 2009-09-09
Also published as: WO2008064872A3; WO2008064872A2; DE102006056451A1; US20100035210A1; JP2010510842A

Abstract

The invention relates to a method for producing a dental product, according to which a moulding, in the form of a negative mould, of a tooth or a tooth stump is created using a moulding material, and this negative mould is scanned. The scanner result is then used to mechanically produce the dental product. In order to improve the scanner result, either the surface of the moulding is roughened, or a scannable moulding material containing between 0.01 and 80 wt.% of titanium dioxide, zirconium dioxide, zinc oxide and/or barium sulfate and black colouring pigments, is used.

Description

Process for producing a dental product and scannable material

The invention relates to a method for producing a dental product, for example a crown or bridge, wherein first an impression is made as a negative mold of at least one tooth or tooth stump with an impression material and then the dental product is produced by machine. Furthermore, the invention relates to an impression material which is suitable for use in such a method.

The production of dental products using CAD and / or CAM methods is known in dentistry. For this purpose, for example, exists. Under the name ^® CEREC 3 system, a camera system of the Sirona Dental Systems GmbH, with which intraorally detects the dental situation after the grinding of a tooth and a dental product is generated automatically based on the determined data in this case. Regardless of the fact that the scanning of a dental situation is sometimes perceived as difficult due to the limited space in the patient's mouth, in this system the prepared tooth and the adjacent teeth must be optically surface-optimized with a white powder spray in order to achieve a sufficient result. This sometimes leads to problems, since even the smallest amounts of moisture can change the surface of the powder layer and also the uniform spraying of cavities in molars can be difficult. These sources of error can in particular result in a deterioration of the edge closure of a restoration.

DE 103 39 247 A1 proposes a method for producing a dental restoration, in which an impression of the oral situation is scanned as a negative form, dispensing with the provision of a positive model, the result of the scan being used for the mechanical production of the dental model. Restoration is used. The mechanical scanning of this negative model is particularly disadvantageous in the area of undercuts. Even with an optical scan of the negative model often enough information can not be obtained for the exact reproduction of all details. In particular, the detection of edges and unfavorable angular positions in an optical scanning is difficult. The optical scanning is therefore felt to be in need of improvement.

In order to be able to optically scan or grasp molded bodies as accurately as possible, DE 100 38 564 A1 proposes a composition for producing a shaped body to which a metal powder, a powder of a metal alloy or a powder of a pigment with a metallic effect is admixed. However, it has been found that even with the use of such a mass, the scanner results are sometimes perceived as unsatisfactory, since an exact reproduction is not always possible. In addition, this material is only suitable for impressions in the range of about 1 to 2 mm, which are used for example in the bite registration.

The present invention is based on the object to provide a method and an impression material to be used in this case, which allows good handling a reproducible high quality and accuracy of a dental product produced using a scanning result.

This object is achieved essentially by the fact that in a method of the type mentioned at least part of the surface of the impression of a tooth or tooth stump is roughened before the roughened impression scanned by negative mold and then machined using the result of the scanner a dental product becomes. The invention is based on the idea that the roughening of the surface The impression leads to a matting, which significantly improves the scanner result. In this way, impressions with a depth of more than 2 mm can be easily scanned and dental products produced with high accuracy using the result of the scan.

According to a preferred embodiment of the invention, the roughening of the surface of the impression takes place by means of laser irradiation, splatter method, vapor deposition, plasma method sandblasting and / or powder jet method. When sandblasting is a method in which z. B. rough quartz sand is sprayed with compressed air to the negative mold. In contrast, in a powder jet method finer sand, z. As sodium bicarbonate, sprayed to achieve a roughening of the surface of the impression to improve the scanning ability. Both the sandblasting and the powder jet method have the advantage that such devices are present in the laboratory or at the dentist, so that no additional investments in a dental practice are incurred. Consequently, a dentist does not have to learn any new procedures. In particular, devices for the powder jet method, with which usually coverings are removed on the tooth, are usually present at each dental chair of a dental practice.

Both a mechanical scanning and a non-contact scanning of the roughened impression are suitable for the method according to the invention. However, it is preferred if the scanning of the roughened impression takes place without contact. This can be done for example by a laser scan, a fringe projection or with a CCD camera. It is particularly preferred if the non-contact scanning with the above-mentioned CE-REC 3 System ^® Sirona Dental Systems GmbH, wherein the software that is usually used to scan a positive model, is adapted to the inventive method to instead of sublime impres- sions, ie a negative form, to scan. For the production of a crown or bridge as a dental product, it is preferred if the at least one tooth or tooth stump is shaped only after the grinding, ie after the preparation, and this negative form is roughened and subsequently scanned. Alternatively, however, it is also possible for an impression to be created first of the original tooth situation, the data of which is used to produce the outer contour of the dental product, while after the preparation a further impression is taken, the data for producing the inner contour of the dental product be used.

Especially with heavily destroyed teeth, it is not useful to make an impression of the original tooth situation. In such cases, taking into account the result of the scan, a pattern is selected from a database, in particular an image database, and this image is used to produce the dental product using the result of the scan.

The mechanical production of the dental product is then preferably carried out in a CAD and / or CAM process. In this way, dental products can be manufactured with high precision in an automated and cost-effective manner.

In some applications it may be necessary to split the impression into several layers before scanning, which are then scanned one at a time, assembling the scans of the individual layers by means of matching software. From the data of these layers thus a virtual model is created, which is used for the production of the dental product.

A significant advantage of the method according to the invention is that in some cases conventional impression materials for creating the negative mold can be used, which are then scanned after roughening. Since every dentist is familiar with the handling of impression materials, no new techniques need to be learned and no special equipment must be provided.

The object underlying the invention is further achieved by a particularly optically scannable impression material which is suitable for producing an impression of at least one tooth or tooth stump, wherein the impression material contains 0.01 to 80% by weight of titanium dioxide, zirconium dioxide, zinc oxide and / or barium sulfate , The impression material may essentially be a known, irreversibly crosslinking impression material that is elastically deformable in the cured state. Particularly suitable for this purpose are alginates, condensation-crosslinking and addition-crosslinking silicones, addition-crosslinking aciridino polyethers, addition-crosslinking silico-polyethers, condensation-crosslinking alkoxy-silyl polyethers, polysulfides and polyethers or silicones crosslinking via metathesis reaction. In particular, this impression material Panasil ^® chain Bach GmbH & Co. KG is. It has been found that the scanning result can be further improved if the impression material contains about 0.1 to 70% by weight, in particular 1 to 20% by weight and particularly preferably about 2 to about 15% by weight of titanium dioxide, zirconium dioxide, zinc oxide and / or or barium sulfate. According to a preferred embodiment, the impression material contains at least 10% by weight of titanium dioxide, zirconium dioxide, zinc oxide and / or barium sulfate.

The above-mentioned substances brighten up the impression material, whereby too much lightening can sometimes lead to weak contrasts. Therefore, it is preferred if the impression material contains in particular black color pigments, dyes applied to a carrier material and / or oil-soluble and / or polymer-soluble dyes. As a result, for example, a gray tint of the negative form is achieved, which is particularly suitable for optical scanning. The abovementioned pigments, which improve the scannability of the impression compound by brightening and altering the contrast, can be combined with the customary reinforcing and non-reinforcing fillers.

Pigments in the context of the present invention are inorganic and organic virtually insoluble colorants which have a refractive index equal to or greater than 1.7.

In the context of the present invention, a filler is understood as meaning a substance which influences the properties of the impression material in terms of hardness, strength, elasticity and elongation and has a refractive index of less than or equal to 1.7. These may be reinforcing fillers or non-reinforcing fillers or mixtures thereof.

Particularly suitable as reinforcing fillers are highly dispersed, active fillers having a BET surface area of at least 50 m ² / g. Particularly suitable are those having a single particle size in the nanometer range, which may be present as aggregates and / or agglomerates. Preferred reinforcing fillers are substances selected from the group consisting of aluminum hydroxide, aluminum oxide, calcium carbonate and sulfate, silicon dioxide, silicates such as talc, clay and mica, as well as precipitated and / or fumed silica. Of course, the abovementioned compounds can be used individually or in any combination with one another, and also in both hydrophilic and hydrophobicized form.

In principle, the same substances as for the reinforcing fillers are suitable as non-reinforcing fillers, although the non-reinforcing ones have necessarily a BET surface area of less than 50 m ² / g (publication series "Pigments Degussa"). acids, number 12, page 5 and number 13, page 3). Preferred non-reinforcing fillers are substances which are selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, alkaline earth metal fluorides, alkaline earth metal carbonates, calcium apatite (Ca ₅ [(F, Cl, OH, / 2CO ₃ ) I (PO-O ₃ ], in particular calcium hydroxyapatite (Ca ₅ [(OH) ₁ (PO ₄ ) ₃ ], aluminum hydroxide, alumina, silica, precipitated silica and calcium carbonate.) Of course, the compounds mentioned above can be used individually or in any combination with each other, including both hydrophilic and inorganic hydrophobicized form.

In a preferred embodiment, the impression material of the invention is based on alginates, condensation-crosslinking and / or addition-crosslinking silicones, addition-crosslinking aciridino-polyethers, addition-crosslinking silico-polyethers, condensation-crosslinking alkoxy-silyl polyethers, condensation-crosslinking polysulfides and polyethers crosslinking via metathesis reaction. or metathesis crosslinking silicones, and comprises pigments in the form of a combination of contrasting pigments and brightening pigments, the latter containing titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide.

In a particularly preferred embodiment, the impression material according to the invention is in the form of a 2-component dental impression material based on addition-crosslinking silicones with components A and B. Component A contains an organopolysiloxane having at least two ethylenically unsaturated groups and a hydrosilylation catalyst, and component B contains an organohydrogenpolysiloxane. Further, components A and / or B contain pigments in the form of a combination of contrasting pigments and lightening pigments, the latter containing titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide. The organopolysiloxane having at least two ethylenically unsaturated groups is preferably a vinyl-containing polydimethylsiloxane, which may optionally be in the form of a mixture of various vinyl-containing polydimethylsiloxanes. The viscosity of the organopolysiloxanes is usually less than 180,000 mPa-s at 20 ⁰ C, preferably from 20 to 165,000 mPa-s at 20 ⁰ C.

The hydrosilylation catalyst is preferably a platinum catalyst.

The organohydrogenpolysiloxane is preferably a polymethylhydrogensiloxane, which may optionally be present in the form of a mixture of different polymethylhydrogensiloxanes. Organohydrogenpolysiloxanes having an Si-H content of 0.01 to 15 mmol / g are used.

The brightening pigments used are preferably pigments which have a doping and / or superficial coating of titanium dioxide, zinc oxide, barium sulfate and / or zirconium dioxide, and the inorganic white pigments in the form of metal oxides, metal hydroxides, metal oxide hydrates, metal carbonates, metal silicates or metal sulfates of the metals magnesium , Calcium, strontium, barium, boron, aluminum, silicon, titanium, zinc. These lightening pigments were doped with titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide during the production process and / or were provided on the surface with a layer of titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide.

The proportion of lightening pigments in the dental impression material according to the invention is from 10 to 80% by weight, preferably from 15 to 80% by weight, based on the dental impression material. As contrasting pigments, pigments are used which are dark in color, preferably black or black-gray. These are preferably dark-colored pigments which are selected from the group of metals, carbon, in particular carbon black and / or graphite, metal oxides, metal hydroxides, metal oxide hydrates, metal silicates, sulfur-containing metal silicates, metal sulfides, the metal cyanides, the metal selenides, the metal chromates, the Metallmolybdate and the insoluble or insolubilized by laking or applied to inorganic pigments organic dyes. These contrast-providing pigments are to be used in such a form, for example, in a sufficiently sized grain size and a suitable grain shape, the desired contrast-enhancing effect is achieved.

The proportion of contrast-producing pigments in the dental impression material according to the invention is less than 1% by weight, preferably less than 0.1% by weight and more preferably between 0.0001 and 0.01% by weight, based on the dental impression material.

Particularly preferred lightening pigments have a stabilization and / or surface coating with zirconium dioxide.

Impression materials which have a proportion of at least 10% by weight, in particular of at least 15% by weight, based on the total weight of the dental material, of contrasting pigments are preferred.

The impression materials according to the invention preferably have a combination of contrasting pigments and brightening pigments, which is selected such that the impression materials when examined with the CEREC measuring system in the cured state have brightness values of> 90% and contrast. contrast values of> 90%, measured in comparison to the reference material zirconium oxide.

In a further preferred embodiment, the impression materials according to the invention have a combination of contrasting pigments and brightening pigments, which is selected such that the impression materials when examined with the L * a * b * color measurement system in the cured state have L values of> 80, preferably> 85, in particular> 90 and in investigations of the scanning ability with the CEREC measuring system in the cured state have brightness values of> 90% and contrast values of> 90%, measured in comparison to the reference material zirconium dioxide.

The impression material according to the invention is preferably used for the production of dental products, such as bridges, crowns or dental prostheses, and very particularly preferably as a bite registration material. The invention also relates to these uses.

The invention will be explained in more detail with reference to the embodiments and with reference to the drawings. All of the described and / or illustrated features alone or in any combination form the subject matter of the invention, regardless of their combination in the claims or their dependency.

The single FIGURE shows a comparison of the gap dimensions and weights of soft samples, which were prepared by a conventional method (Comparative Example 1) and by the inventive method according to Example 1. Comparative Example 1 Production of an Inlay by Intra-Oral Scanning with the CEREC 3 ^System®

Of a standard preparation of a Frasacozahn (tooth 36, Frasaco GmbH), a model was generated by the standard preparation after spraying with Dentaco scan spray (Dentaco Dentalindustrie- and Marketing GmbH) was scanned with the CEREC 3 System ^® (Sirona Dental Systems GmbH) ,

From the virtual model generated by this method, a two-layer inlay was constructed and milled from a Mark II ceramic blank (VITA Zahnfabrik H. Rauter GmbH & Co. KG). Of the inlay five SOFTPRO produced ben by filling the cavity with Panasil ^® contact plus (Kettenbach GmbH & Co. KG) and the inlay was inserted into the filled cavity. The soft samples thus reflected the gap left between the inner wall of the cavity and the outer wall of the inlay, which is a measure of the accuracy of the inlay.

These soft samples were placed in plastic (PalaXpress ^®, Heraeus Kulzer GmbH) and then poured ground horizontally and vertically in different planes. These levels were measured under a microscope. In addition, the gap volumes were calculated from the weight of the soft samples. In this case, a gap width of 90 microns and a gap volume of 7.67 mm ^{3 was} achieved.

Example 1 (Inventive): Preparation of an inlay by scanning a negative mold with a modified CEREC 3 ^System®

From the same standard preparation on a Frasacozahn (Zahn 36, Frasco GmbH) as in Comparative Example 1, an impression with an invented to the invention impression material based on the impression material Panasil ^® (Kettenbach GmbH & Co. KG) taken.

The surface of this impression was matted for 30 seconds using a powder jet method (eg, Prophyflex Kavoprophypearls, KaVo Dental GmbH). Subsequently, this negative form was recorded with a modified CEREC 3 ^System® (Sirona Dental Systems GmbH), the software being modified in such a way that impressions could be scanned in place of raised areas.

As in Comparative Example 1, a two-layer inlay was constructed from the virtual model thus produced and milled from a Mark II ceramic blank (VITA Zahnfabrik H. Rauter GmbH & Co. KG). Turn five soft samples were prepared from the inlay by filling the cavity with PANA sil ^® contact plus (Kettenbach GmbH & Co. KG) and the inlay was inserted into the filled cavity.

The soft samples were placed in plastic (PalaXpress ^®, Heraeus Kulzer GmbH) poured and then ground down horizontally and vertically in different planes and measured. The gap width was 77 μm and the gap volume 7.50 mm ³ .

As a result, the optical images of the impression taken with the camera of the CEREC 3- ^{System® produced} very accurate results. At the same time, sources of error that may occur during intraoral uptake could be circumvented. Example 2 (Inventive) and Comparative Examples 2 to 4:

The ingredients required for scanning in example 2 according to the invention had the following technical data:

a.) ZrO ₂ coated titanium dioxide

TiO ₂ content 94% inorganic aftertreatment zirconium dioxide

Particle size 0.24 μm specific gravity 4.05 g / cm ³

Loss at 105 ⁰ C 0.6%

Ramming weight 1, 2 g / cm ³

Oil number (g / 100g pigment) 18

Water requirement (cm ³ / 100g pigment) 28

b.) Black color batch

Chemical characterization Graphite powder suspended to 20% in

silicone polymers

Particle size <20 μm

Form pasty

Color black, L *: 3.47, a ^* : 0.22, b *: 0.08

Melting point / melting range - 50 ^° C.

Boiling point / boiling range> 200 ° C

Flash point 210 ⁰ C (DIN 51376)

Ignition temperature 480 ⁰ C (DIN 51794)

Vapor pressure at 20 ° C approx. 6 hPa, at 50 ° C approx. 18 hPa

Density at 20 ° C approx. 0.98 g / cm ³

Viscosity 23 ° C dynamic 14,000-36,000 mPa s

(Haake / Brookfield) Example 2: Scannable Bite Registration Material (According to the Invention)

catalyst paste

In a closed kneader, 53 parts of cristobalite fine flour with a mean grain size of 7 microns, 3 parts of a pyrogenically prepared, highly dispersed hydrophobicized silica having a BET surface area of 150m ² / g, 0.3 parts of zeolite (molecular sieve), 15 parts ZrO 2 coated TiÜ ₂ with the particle size of 0.24 microns, 25 parts Divinylpolydimethylsiloxan with a viscosity of 50 mPa-s measured at 20 ⁰ C, 2.5 parts of trimethysiloxypolydimethylsiloxane, 0.6 parts of platinum catalyst and 0.1 parts of a Fettalkoholethoxylates homogenized for 2 hours and then degassed for 15 minutes in vacuo.

A white medium-flowing paste (ISO 4823) was obtained. The paste provided the component A of the two-component silicone material of the invention. After storage at 60 ⁰ C for one month were the viscosity and the reactivity in the desired range.

base paste

In a closed kneader 53 parts of cristobalite fine flour with a mean grain size of 7 microns, 2.5 parts of a pyrogenically prepared, highly dispersed hydrophobized silica having a BET surface area of 150rτv7g, 0.06 parts of the black colorant, 15 parts ZrO ₂ coated TiO ₂ with the particle size of 0.24 .mu.m, 20.5 parts Divinylpolydimethysiloxan with a viscosity of 50 mPa-s measured at 20 ⁰ C, 7 parts Polymethylhydrogensilo- xan with a viscosity of 50 mPa-s measured at 20 ⁰ C, 2 parts Trimethysi - Loxypolydimethylsiloxan and 0.15 parts of a fatty alcohol ethoxylate homogenized for 2 hours and then degassed for 15 minutes in vacuo. A white medium-flowing paste (ISO 4823) was obtained. The paste provided the component B of the two-component silicone material of the invention. After storage at 6O ⁰ C for one month were the viscosity and the reactivity in the desired range.

mixture

50 parts of components A and B were expressed from a cartridge (Mixpac) and mixed homogeneously by means of a static mixer (Mixpac).

The product remained processable at room temperature for approximately 15 seconds and completely cured at a temperature of 35 ° C within 60 seconds of the start of mixing.

As Vulkanisat white, hard, difficult to compress moldings were obtained, which, however, were very well beschneidbar.

The bite registration material was examined in its color using the CIELAB method with a Konica Minolta colorimetric system and its scanning capability with the CEREC camera system. The results are shown in Table 1.

This example demonstrates that the use of zirconia-coated titanium dioxide in combination with a contrasting dark colored pigment results in contrast and brightness values that are very close to the ZrO ₂ reference material, thus resulting in excellent scanning capability in the CEREC system. Comparative Example 2: Bite registration material Metalbite® Fa. R-Dental (not according to the invention)

A commercial bite registration material Metalbite® from R-Dental (Lot. 6403750) based on addition-crosslinking vinylpolysiloxanes was mixed according to the manufacturer's instructions and allowed to set.

The product was processable at room temperature for about 30 seconds and completely cured at a temperature of 35 ° C within about two minutes of the start of mixing.

This example shows that while the use of metal pigments can provide a good contrast, it results in a relatively large loss in brightness and dynamics, resulting in unfavorable results when scanning with the CEREC camera.

Comparative Example 3: Bite registration material Stonebite Scan® from Dreve (not according to the invention)

A commercial bite registration material Stonebite Scan ® Fa. Dreve (Lot. 602143/602147) based on addition-crosslinking vinylpolysiloxanes was mixed according to the manufacturer's instructions and allowed to set. The product was processable at room temperature for about 30 seconds and fully cured at a temperature of 35 ° C within about two minutes of the start of mixing.

This example shows that gray coloration can achieve very good contrast, but results in a relatively large loss in brightness and dynamics, and thus leads to unfavorable results when scanning with the CE-REC camera.

Comparative Example 4: Bite registration material Vanilla Bite® Fa. Discus Inc. (not according to the invention)

A commercially available, non-scanning bite registration material Vanilla Bite® Fa. Discus Inc. (Lot. 06068001) based on addition-crosslinking vinylpolysiloxanes was mixed according to the manufacturer's instructions and allowed to set.

The bite registration material was examined in its color using the CIELAB method with a Konica Minolta colorimetric system and its scanning capability with the CEREC camera system. The results are shown in Table 1. This example shows that a white non-scanning bite registration material can achieve some brightness in the L * a * b * color measurement, which is a requirement for scanning, but no contrast is produced when scanning with the CEREC camera system which can lead to unfavorable scanning results.

Measuring method / measuring device

The product was measured with a CEREC 3 camera (Sirona) against a CE-REC ZrO ₂ standard from Sirona. For this purpose, a test specimen in the dimensions 4.8 / 16.9 / 19.4 mm was created and inserted into a camera attachment, wherein a precisely predetermined distance of the surface is defined to the scan camera.

The material was measured with the Sirona software version 2.80 R228015 CEREC inLab.

As a result, three parameters were output, namely brightness, contrast and dynamics, where the dynamics are calculated from the product of contrast and brightness divided by one hundred.

The result thus provides information about the scannability of the material or its surface, whereby values of 100% for contrast, brightness and dynamics mean optimum scannability. Table 1: Comparison of scanner results

Reference ZrO ₂ -> Contrast 100 / Brightness 100 / Dynamic 100

¹⁾ measured in comparison to the CEREC zirconia standard with the CEREC 3 camera system with software version 2.80 R228014 CEREC InLab from Sirona.

²⁾ Color value measured in reflection mode without gloss component (SCE) with the Konoca-Minolta colorimeter Spectrophotometer CM-3500d.

Claims

Claims:

1. A process for producing a dental product, in particular a crown or bridge, comprising the following steps:

Producing an impression as a negative mold of at least one tooth or tooth stump with an impression material,

Roughening at least part of the surface of the impression,

Scanning the roughened impression as a negative mold and

automated production of a dental product using the result of the scan.

2. The method according to claim 1, characterized in that the roughening of the surface of the impression by means of sandblasting and / or powder jet process takes place.

3. The method according to claim 1, characterized in that the roughening of the surface of the impression takes place by means of laser irradiation, splatter method, vapor deposition and / or plasma method.

4. The method according to any one of claims 1 to 3, characterized in that the scanning of the roughened impression takes place without contact.

5. The method according to any one of the preceding claims, characterized in that the at least one tooth or tooth stump after grinding (preparation) is molded.

6. The method according to any one of the preceding claims, characterized in that for the mechanical production of the dental product using the result of the scan from a database, a pattern of a dental product is selected and manufactured.

7. The method according to any one of the preceding claims, characterized in that the mechanical production of the dental product takes place in a CAD and / or CAM method.

8. The method according to any one of the preceding claims, characterized in that the impression is divided into several layers prior to scanning, which are then scanned individually, the scanner results of the individual layers are put together by means of software.

9. Use of an impression material for producing a dental product in a method according to one of the preceding claims.

10. Use of the impression material according to claim 9 as Bissregistriermaterial.

11. Scannable impression material for producing an impression of at least one tooth or tooth stump, characterized in that the impression material from 0.01 to 80 wt.% Titanium dioxide, zirconium dioxide, zinc oxide and / or barium sulfate and black color pigments, applied to a substrate dyes and / or oil and / or polymer-soluble dyes.

12. impression material according to claim 11, characterized in that it contains 0.1 to 70 wt.%, In particular 1 to 20 wt.%, Preferably 2 to 15 wt.% Titanium dioxide, zirconium dioxide, zinc oxide and / or barium sulfate.

13. impression material according to claim 11 or 12, characterized in that it contains at least 10 wt.% Titanium dioxide, zirconium dioxide, zinc oxide and / or barium sulfate.

14. Impression material, characterized in that the impression material is based on alginates, condensation-crosslinking and / or addition-crosslinking silicones, addition-crosslinking aciridino polyethers, addition-crosslinking silico-polyethers, condensation-crosslinking alkoxy-silyl polyethers, condensation-crosslinking polysulfides and Me polyethers and / or metathesis reaction-crosslinking silicones, and pigments in the form of a combination of contrasting pigments and lightening pigments, the latter containing titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide.

15. impression material according to claim 14, characterized in that the impression material in the form of a 2-component Dentalabformmaterials based on addition-silicones with components A and B is present in component A an organopolysiloxane having at least two ethylenically unsaturated groups and a hydrosilylation catalyst, containing in component B, an organohydrogenpolysiloxane and containing in component A and / or B pigments in the form of a combination of contrasting pigments and brightening pigments, the latter titanium dioxide, zinc oxide, barium sulfate and / or zirconium dioxide.

16. Impression material according to one of claims 14 to 15, characterized in that the lightening pigments are inorganic white pigments in the form of metal oxides, metal hydroxides, metal oxide hydrates, metal carbonates, metal silicates or metal sulfates of the metals magnesium,

Calcium, strontium, barium, boron, aluminum, silicon, titanium, zinc which have been doped during the production process with titanium dioxide, zinc oxide, barium sulfate and / or preferably zirconium dioxide and / or on the surface with a layer of titanium dioxide, zinc oxide, Barium sulfate and / or preferably zirconium dioxide were provided.

17. impression material according to any one of claims 14 to 16, characterized in that the contrast-producing pigments are dark in color and are selected from the group of metals, of carbon, in particular of carbon black and / or graphite, the metal oxides, the metal hydroxides, the Metal oxide hydrates, the metal silicates, the sulfur-containing metal silicates, the metal sulfides, the metal cyanides, the metal selenides, the metal chromates, the Metallmolybdate and the insoluble or unsolubilized or aufziege on inorganic pigments organic dyes and in an amount less than 1

% By weight, preferably less than 0.1% by weight and more preferably between 0.0001 and 0.01% by weight, based on the dental impression material.

18. impression material according to any one of claims 14 to 17, characterized in that the lightening pigments have a doping and / or superficial coating with zirconium dioxide and in a proportion of at least 10 to 80 wt.%, In particular of at least 15 to 80 wt.% , based on the total mass of the dental material, are used.

19. Impression material according to claim 14, characterized in that when examined with the CEREC measuring system in the cured state has brightness values of> 90% and contrast values of> 90%, measured in comparison to the reference material zirconium dioxide.

20. Impression material according to claim 14, characterized in that said at examination with the L ^* a * b * -colour measurement system in the cured state L-values of> 80 preferably> 85, in particular> 90, and in studies of scannability with the CEREC measuring system in the cured state has brightness values of> 90% and contrast values of> 90%, measured in comparison to the reference material zirconium dioxide.